This invention relates to a push-on type electrical connector (referred to as "push-on connector" hereinafter).
The applicant of this application proposed a push-on connector disclosed in Japanese Utility Model Application Laid-open No. 63-164,183. The disclosed push-on connector applied to a coaxial connector will be explained by referring to FIG. 3 and FIGS. 4a, 4b and 4c.
As shown in the drawings, a connector plug 20 includes, between a coupling 23 and a plug body 22, a slide ring 24 whose diameter is so determined that its forward end is urged by the stopper 13 provided along the forward end of the socket 12 of a connector receptacle 10. A spring 26 is provided between the slide ring 24 and the plug body 22 to urge the slide ring 24 towards the connector receptacle 10, while the coupling 23 is formed at its forward end with a latch portion 231. The coupling 23 is slidable rearward on the plug body 22 against the force of the spring 26. The forward movement of the coupling 23 is restricted by an abutment of its rear latch portion 232 against one edge of C-shaped spring ring 28.
The term "forward end" used herein is intended to designate the end of a member of the connector plug 20 nearer to the mating connector receptacle 10 or the end of a member of the connector receptacle 10 nearer to the mating connector plug 20 when the connector plug 20 and the connector receptacle 10 are arranged about to be connected to each other as shown in FIG. 3. Whereas the "rear end" means opposite sense.
On the other hand, the slide ring 24 is formed on its outer circumference with an anchoring portion 241 for regulating the position of the slide ring 24 with the aid of the latch portion 231 of the coupling 23. As a result, the slide ring 24 is always positioned to cover the anchoring recess 25 formed in the outer circumference of the plug body 22.
As shown in FIG. 3, the connector plug 20 further includes along its axial line a center contact 21 fitted therein through an insulating sleeve, while the connector receptacle 10 includes along its axial line a center contact 11 fitted therein through an insulating sleeve. The socket 12 is formed with a plurality of slits 14 circumferentially spaced and extending in the axial direction and has a spring ring 15 thereon for increasing the springy force of the socket 12.
With this arrangement, the connector plug 20 is held with the coupling 23 grasped by one hand of an operator and is then inserted into the receptacle 10 (FIG. 4a), the stopper 13 of the connector receptacle 10 rides on the outer circumference of the plug body 22 and the forward end of the slide ring 24 is urged rearward against the force of the spring 26 by the stopper 13 of the connector receptacle 10. In this state, the contact 11 is fitted in the contact 21 to establish the electrical connection between them.
By further inserting the connector plug 20 into the connector receptacle 10, the slide ring 24 is retracted toward the cable holding portion 27 as shown in FIG. 4b and the stopper 13 is then engaged in the exposed anchoring recess 25 to reduce the outer diameter of the socket 12 as shown in FIG. 4c. At the same time, the stopper 13 disengages from the forward end of the slide ring 24 so that the slide ring 24 returns to its original position with the aid of the force of the spring 26, with the result that the slide ring 24 covers the stopper 13 to prevent it from removing from the anchoring recess 25. The electrical connection and locking of the connector are completed in this manner.
In disconnecting the connector, the connector plug 20 is pulled away from the connector receptacle 10 with the coupling 23 grasped by one hand of the operator so that the slide ring 24 is retracted by the latch portion 231 of the coupling 23 engaging the anchoring portion 241 toward the cable holding portion 27 against the spring force of the spring 26 to expose the anchoring recess 25. By further pulling the connector plug 20 from the connector receptacle 10, the stopper 13 is removed from the anchoring recess 25 to release the lock and disconnect the electrical connection between the contacts 11 and 21.
The push-on connector of the prior art described above has the advantage in that only the operation of the coupling 23 can perform the electrical connection and disconnection and the locking between the connector plug 20 and the connector receptacle 10. On the other hand, however, it involves a following problem in use.
In inserting the connector plug 20 into the connector receptacle 10, at the moment when the stopper 13 of the connector receptacle 10 has just abutted against the forward end of the slide ring 24 (FIG. 4a or 4b), the abutment "feeling" is often mistaken for a completion of the locking of the connector by the operator. In this case, therefore, the connector is then used for the inherent purpose without further insertion of the slide ring 24 or without locking the connector plug 20 and the connector receptacle 10.
If such a connector which is not completely locked and is used in an environment subjected to relatively violent vibrations such as a vehicle, the connector plug 20 tends to be dislodged from the connector receptacle 10 in use to cut the signal line associated therewith suddenly. In the push-in connector of the prior art, therefore, it is impossible to confirm in a reliable and easy manner whether the connector plug and the connector receptacle are completely locked or not.